Blower valve control arrangement



E. B. LEAR $643,640 BLOWER VALVE CONTROL ARRANGEMENT 2 Sheets-Sheet l June 30, 1953 Filed Jan. 28, 1950 NNN R \N lll xwmw

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he a Q N R E. B. LEAR BLOWER VALVE CONTROL ARRANGEMENT June 30, 1953 2 Sheets-Sheet 2 Filed Jan. 28, 1950 LU H E g Q INVENTOR 13/424 6 154A.

ATTO R N EY Patented June 30, 1953 Earl B. Lear, Detroit, Mich., Pneumatic Tool Company, corporation of New Jersey assignor to Chicago New York, N. Y., a

Application January 28, 1950, Serial No. 141,083

10 Claims.

This invention relates to rock drills of the pneumatic percussive type, and more particularly to an improved control for a blower valve arrangement for use when it is desired to blow cuttings and sludge from the bottom of a deep hole.

An object of the invention is the provision of an improved control-arrangement whereby the blower valve can be automatically locked in blowing position and released therefrom by a simple manipulation and at a distance remote from the drill. The invention is especially suited for wagon drills which are so arranged that the blower valve is often out of reach of the operator.

A feature of the invention is a handle pivotally connected to the blower valve in such manner that the operator, by pulling a. cable forwardly of the drill may turn the blower valve to blowing position wherein it is automatically locked, and by pulling the cable somewhat laterally of the drill, may release the blower valve for automatic restoration to drilling position. Another feature resides in the use of an adjustable torsion spring for resisting such forward movement, and a separate compression spring for resisting lateral movement.

Other objects and features of the invention will appear more clearly from the description to follow, when considered in connection with the accompanying drawings wherein:

Fig. 1 is a longitudinal section of a fragmentary portion of a rock drill embodying the invention, and showing the blower valve in blowing position;

Fig. 2 is a cross-section of a fragmentary portion of a rock drill showing the blower valve in drilling operation;

Fig. 3 is a plan view of the blower valve arrangement showing the handle in drilling position;

Fig. 4 is anend view of the blower valve arrangement as seen from line 44 in Fig. 5;

Fig. 5 is a cross-section View of the blower valve arrangement, looking rearward as seen from line 5-5 in Fig. 1;

Fig. 6 is a view of 'a 'return'spring used in the blower valve arrangement;

Fig. 7 is an end view of the blower valve arrangement as seen from the right of Fig.5;

Fig. 8 is a cross-section fragmentary view of the blower valve arrangement showing the handle in blowing position;

Fig. 9 is a cross-section view similar to that'of Fig. 8, but showing the handle just after clearing a blowing position slot in a bushing used in the blower valve, but before being moved to drilling position;

Fig. 10 is a perspective view of a bushing in the blower valve arrangement, and

Fig. 11 is a perspective view of the blower valve.

Referring now to the drawings and more par-- ticularly to Fig. 1, the rock drill comprises a cylinder l0 providing a piston chamber II in which a hammer piston I2 is caused to reciprocate. Integral with the lower portion of the used cylinder ID is a guide lug arrangement l3, which is slidably maintained in a shell (not shown) for the mounting of the drill. In a wagon drill assembly, which is not shown, but which is familiar to those skilled in the art, the shell is supported by a universal-type connection so that the drill can be operatively maintained in any vertical or horizontal position. A rotation mechanism for imparting 'step-by-step rotary movement to the piston l2 is arranged at the rearward end of the cylinder and comprises a rifle nut l4 threadably secured within the piston, a rifle bar plurality of helical splines engaging the rifle nut, a head It on the rifle bar, a series of pawls I1 carried by the head, and a stationary ratchet ring it surrounding the head and pawls. The ratchet ring is supported by the cylinder I0 and by a back head l9 rigidly secured to the cylinder by draw bolt means (not shown).

Located in the rear end of the cylinder I0 is a counterbore 2B in which is arranged a valve chest comprising a cylindrical valve cap 2| and a cylindrical valve block-22. The valve cap 2| is provided with a plurality of ports 23 for supplying motive fluid to the rear portion of piston chamber I I, while the valve block 22 has a pair of grooves 25 and 2t adjacently disposed about the inner periphery'thereof, and a plurality of ports 21 extending inwardly from an annular groove 28 arranged on the'rear face of the block. Ratchet ring it abuts against the rear end of valve block 22, and has a series of ports 29 which provide passage for the motive fluid from an annular groove 3| located on the enclosed face of the back head l9, said "groove receiving the motive fluid by way of a passage t2 Which is connected to a throttle valve 33 positioned within the back head. A key 34 is arranged to lock the valve block 22 and ring I8 against rotational movement.

Surrounding the rearward portion of the rifle bar It is a bushing 35 which is supported at its frontend by the valve cap 2! and at its rear end by the valve block 22. A cylindrical distributing valve 36 is spaced from the bushing 35 and is slidingly supported for reciprocal movement within the valve cap 2i and valve block 22, and has a flange 31 on its outer periphery. Supply passageways '38 and-e9 formed in the wall *0! l5 having a' cylinder 18, extend from groove 25 to the forward portion of the piston chamber H. A groove 40, formed on the external surface of valve 36. connects groove 26 to the atmosphere by way of groove 25, a passageway 4| and port 42, to exhaust air from the chamber H in front of piston l2. A passageway 43, formed in the wall of cylinder l9, extends from the rear face of the distributing valve flange 37 to the portion of the piston chamber H defined in part by the rear face of piston l2. Another passageway 44 extends from the front face of distributing valve flange 31', through the valve block 22 and cylinder wall, to a blower valve arrangement 45. A relief port 46 is arranged to vent the rear face'of distributing valve flange 3i, while a cylinder exhaust groove :31 connects the piston chamber, in the region of midportion, to the blower valve arrangement 45.

The exhaust groove 41 is located so that it is uncovered by the piston during both the forward and rearward stroke thereof. In accordance with conventional practice, a tube 48, for the conduction of live air to the drill hole, is positioned within the rock drill as shown. Alternatively a water tube may be used. The construction and operation of the distributing valve arrangement are essentially the same as in Craze Patent 2,443,894, June 22, 1948.

For the purpose of cleansing a deep hole which is clogged with detritus beyond the capacity of the air tube supply to remove it, a blower arrangement is provided which stops the drilling operation and diverts the full supply of live air through a hole in the drill steel. As best shown in Fig. 5, the present blower valve arrangement 45 comprises a valve bushing 49, a valve 59, a handle 51 attached to the valve, a retainer washer 52, and a return spring 53, all arranged as hereinafter described. The bushing 49 is press fitted to a bore 54 formed in a wall portion of the cylinder H], transverse to the longitudinal axis of the cylinder. Two elongated slots 55 as well as two holes T5 (Fig. 2) are formed in the body of the bushing 55. One end of the bushing 49 is enlarged and contains at the outer end two circumferential slots 5E and 51, the former being of greater length but of less depth than the latter. At the other end of the bushing is a notch 58 for receiving and anchoring one end of spring 53.

The valve -39 has a pair of grooves 59 and 60, arranged on opposite sides of the body of the valve, the length of groove 59 being equal to that of slot 55, while groove 55 has a width corresponding to the diameter of holes 18. One end of the valve 59 is enlarged and contains a diametrical slot H for the reception of handle 51, which is pivotally maintained therein by a pin 62 extending transversely of the slot. A compression spring 63, arranged within a cavity at one end of the handle 5!, abuts against the bottom of slot 61 and urges the handle about the axis of pin 62 toward an upright position in engagement with either slot 56 or 51 when the valve is positioned in the bushing 59. A bevel 6 3. on the lower inner surface of the handle 5|, permits the handle to be cooked outwardly so that it may be swung out of engagement with slot 51, which is slightly greater in width than the thickness of thehandle, and moved along slot 56. At the other end of the valve 50 a transverse pin 65 is positioned to maintain the washer 52 upon the valve. The washer 52 has a plurality ofradially arranged rounded grooves 66 which seat the ends of pin 55 and a pair of diametrically oppositelongitudinal holes 61, either of which holes may be used to engage one end of spring 53. The washer 52 has a sliding fit on the valve 59 so that cocking thereof is prevented, while precompression of spring 53 urges the washer against the transverse pin 55 with sufficient force to prevent disengagement between the pin 55 and grooves 65. It is to be noted that the arrangement of the grooves 56 allows for the adjustment of the tension of spring 53 to compensate for friction and the weight of a pull rope'or cable 68, which is connected to the handle 5|. Such adjustment is accomplished by merely pushing the washer inwardly along the valve until the grooves 86 are clear of pin 65, and then rotating the washer to either increase or decrease spring tension' as desired.

To'change'from drilling operation to blowing operation the cable 68 is pulled, forwardly, or to the left in Fig. 1. After the initial torsion of spring 53 is overcome, the handle 5! is unseated from the Fig. 2 position and swung forwardly, thus increasing the wind up of the spring. As the handle is being moved, it rides along the shallow slot 55 in rubbing contact with the bottom thereof, due to the action of compression spring 53 on the handle. When the handle reaches the position in Fig. l, and becomes aligned with the deeper slot 57, it drops therein, due to the action of compression spring 55. The operator may then release the pull on the cable and the handle will remain latched in full forward position. To release the handle, the cable is pulled sidewise, swinging the handle out of engagement with slot 57, whereupon the torsion spring 53 causes the handle to swing rearwardly to the Fig. 2 position. When the handle is in blowing position (Fig. 1), groove 59 of the valve 50 connects the cylinder exhaust groove ll to passageway i t; when the handle is in drilling position (Fig. 2), groove 68 of the valve 55 connects passageway it to the atmosphere by way of an exhaust port 69, while groove 55 connects cylinder exhaust groove 4? to the atmosphere by way of exhaust port '5 I.

Referring to Fig. 1, the rock drill shown in blowing position, in which position the distributing valve 36 is at rearward location, thus a1- lowing work medium, such as live air, to pass from the throttle valve 33, through passage 32 and ports 29 in the ratchet ring 18, into groove 28, ports El and onward between the exterior of bushing 35 and interior of distributing valve 36, through ports 23 to the rear end of piston chamber H, then about clearance space between the rifle bar 55 and rifle nut I4 and onward within the body of the hammer piston i2 to a hollow drill steel '72 (fragmentary portion only shown), and therethrough to the drill hole to blow away the detritus. At the same time live air passes from the piston chamber H, through exhaust groove Ill, groove 59 and passageway M, to the front face of valve flange 37, to maintain the valve 38 in rearward position. It is to be noted that the air flowing from the piston chamber i i, through passageway $3, to the rear face of valve flange 3?,

is allowed to bleed to the atmosphere via exhaust ports 58 and 4-2.

When the rock drill is changed from blowing to drilling condition, exhaust groove 3! is connected to the atmosphere by way of groove 59 and exhaust port 7 I, while passageway id is connected to the atmosphere by way of groove 6i: and exhaust port 69. In rotating from blowing position to drilling position, the valve 5% momentarily assumes a position in which the air pressure on the forward face of the valve flange 31 is out off while the air pressure is continued on the rear face of the flange 31, by way of passageway 43, whereupon the valve 36 is shifted forin the piston chamber.

After-the piston l2 has covered the main exhaust groove ll and the passageway 43, and approaches the end of its rearward travel, the entrapped air in the piston chamber, to the rear of piston I2, is compressed and the resulting pressure, which acts on the front edge of the distributing valve 36, is of such degree as to cause the valve to be shifted rearward within the valve chest. Thereupon live air is admitted to the rear of chamber H and piston 52 is driven forward, as explained heretofore.

It is seen that the blower arrangement of the invention provides a means whereby theblower arrangement can be conveniently locked into blowing position and readily released therefrom, and may be operated at a distance remote from the rock drill, and particularly when the drill is mounted in a wagon drill assembly.

What is claimed is:

1. In a rock drill, a blower valve control arrangement comprising a bushing having a plurality of slots, a cylindrical valve member rotatably arranged within the bushing and having a pair of grooves disposed in opposition on the periphery thereof, handle means pivotally aiiixed to the valve member and engageable with end slot means on the bushing to positionally maintain the valve in either of two positions, one of which aligns the bushing slots and the valve grooves whereby the drill is conditioned for blowing operation, the other of which aligns the bushing slots and valve grooves whereby the drill is conditioned for drilling operation, and adjustable resilient means one part of which is affixed to the bushing another part of which engages the valve -member to provide for moving said valve member from blowing position to drilling position upon manipulation of the handle means.

2. In a rock drill, a blower valve arrangement according to claim 1 in which the adjustable resilient means comprises a coil spring which suI- rounds an end of the valve member, a retainer washer, and a transverse pin affixed to the valve and having protruding end portions which engage grooves on the face of the washer.

3. In a rock drill, a blower valve arrangement according to claim 2 in which the end slot means on the bushing comprises a first slot and a second slot, the first slot being of greater circumferential length but of less depth than the second slot, said handle being adapted for sliding contact with either the first or second slot and having resilient means arranged to urge the handle toward sliding contact with the end slot means.

4. In a rock drill, a blower valve arrangement according to claim 3 in which a shoulder is formed between the first and second slot to maintain the handle in the second slot under the influence of the resilient means operating on the handle.

5. In a rock drill, a bushing, a blower valve supported in said bushing for rotation between two extreme positions of stable equilibrium including a normal position and an operated position, a torsion spring interposed between the bushing and valve and constantly urging the latter toward its normal position, a handle connected to the valve to rotate therewith as a unit to turn the valve to operated position, locking means automatically operable upon attainment of the operated position to lock the valve against the.

force of the spring, said handle being mounted for independent movement for releasing the locking means to permit the spring to return the valve to normal position.

6. In a rock drill, a bushing, a blower valve supported in said bushing for rotation between two extreme positions of stable equilibrium including a normal position and an operated position, a torsion spring interposed between the bushing and valve and constantly urging the valve towards its normal position, said blower valve having a radial slot, a handle mounted in said slot to turn the valve against the force of the spring upon being actuated tangentially, said handle being pivoted in the slot to permit the handle to move independently of the valve when actuated laterally, resilient means opposing such independent movement, automatic means including said resilient means for locking the valve in operated position, means for releasing the locking means to permit the torsion spring to restore the valve to normal position, and remote control means for pulling the handle whereby the operator may control the position of the blower valve by pulling the handle either tangentially or laterally.

7. In a pneumatically powered drill having a blower valve arrangement for blowing detritus from a hole being drilled, and including a valve member rotatably positionable for delivery of full line pressure for blowing operations, a control arrangement for the valve member comprising, a lever means pivotally affixed to the valve member and adapted to engage a slot means whereby the valve member is maintained in blowing position, and resilient means disposed between the body of the drill and said valve member and adapted to constantly urge the valve member away from blowing position.

8. In a pneumatically powered drill having a blower valve arrangement according to claim 7, and adjustable means for regulating the tension of the resilient means.

9. In a pneumatically powered drill having a blower valve arrangement according to claim 8, a resilient means for maintaining the lever means in engagement with the slot means.

10. In a pneumatically powered drill having a blower valve arrangement according to claim 9, a remote control means for moving the lever means for placing the valve member in blowing position.

EARL B. LEAR.

References Cited in the file of this patent UNITED STATES PATENTS Number 

